docker build -t dayglo/ansibletower .
or
docker pull dayglo/ansibletower
Go here and get a licence file.
http://www.ansible.com/license
Save it into license.txt somewhere.
docker run -it \
-p 80:80 -p 443:443 \
-v /wherever/you/put/your/license/file/license.txt:/etc/tower/license \
--name tower \
--privileged \
dayglo/ansibletower